As part of the Church Committee’s Senate investigations in 1975, William Colby presented to Committee Chairman Frank Church a gun resembling a Colt .45 equipped with a telescopic sight.

TIME reported “the gun fires a toxin-tipped dart, almost silently and accurately up to 250 ft. Moreover, the dart is so tiny–the width of a human hair and a quarter of an inch long–as to be almost undetectable, and the poison leaves no trace in a victim’s body.”

Church called the pistol “a murder instrument that’s about as efficient as you can get.” TIME revealed “the agency has also developed two other dart-launching pistols, as well as a fountain pen that can fire deadly darts and an automobile engine-head bolt that releases a toxic substance when heated.”